关键词: 激光清洗, 激光焊接, 碳纤维增强热固性复合材料-钛合金异质结构, 连接强度, 失效机制

Abstract: Carbon fiber reinforced thermalsetting composites (CFRTS) and TC4 titanium alloy have high specific strength and rigidity, and have obvious lightweight effect, which are widely used in aerospace and new energy automobile manufacturing. In order to realize the high-strength connection between CFRTS and TC4 titanium alloy, this paper introduces the interface compound control process of "laser cleaning + resin filling". In order to expose the carbon fiber in the CFRTS, we use a pulsed fiber laser to laser clean the surface of CFRTS to remove the epoxy resin on the surface before laser welding of CFRTS and TC4 titanium alloy firstly; A pulsed fiber laser is used to process the surface microtexture of the titanium alloy to increase the contact area between the molten resin and the TC4 titanium alloy during welding and form an "occlusal" structure secondly; Finally a suitable thickness of polyamide (PA) resin is added into contact surface of the cleaned CFRTS and the titanium alloy for laser-assisted welding.In this paper, the influence of laser cleaning process on the joint connection strength is studied. This paper studies the influence of laser cleaning process on the joint strength of joints. Through the comparative analysis of CFRTS surface morphology, PA resin filling conditions, and joint fracture morphology under different laser cleaning process parameters, it is found that laser cleaning CFRTS can significantly enhance the strength of CFRTS-TC4 titanium alloy joint, the maximum shear strength can reach 23.77MPa.

Key words: laser cleaning, laser welding, carbon fiber reinforced thermalsetting composites-titanium alloy heterostructure, connection strength, failure mechanism